Variable speed control for textile carding machines



0. H. RAMO Jan. 23, 1968 VARIABLE'SPEED CONTROL FOR TEXTILE CARDI-NG MACHINES 7 Sheets-Sheet 1 Filed June 25, 1965 INVENTOR OLIVER H. RAMO ORNEYS 0. H. RAMO Jan. 23, 1968 VARIABLE SPEED CONTROL FOR TEXTILE CARDING MACHINES Filed June 25, 1965 7 Sheets-Sheet z INVENTOR OLIVER H. RAMO ATTORNEYS o. H. RAMO 3,364,766

VARIABLE SPEED CONTROL FOR TEXTILE CARDING MACHINES 7 Sheets-Sheet 5 Jan. 23, 1968 Filed June 25, 1965 ATTORNEYS VARIABLE SPEED CONTROL FOR TEXTILE CARDING MACHINES Filed June 25, 1965 O. H. RAMO Jan. 23, 1968 7 Sheets-Sheet 4 lNVE/VTOR.

Jan. 23, 1968 o. H. RAMO 3,364,766

VARIABLE SPEED CONTROL FOR TEXTILE CARDING MACHINES Filed June 25, 1965 '7 Sheets-Sheet 5 F I INVENTOR G 5 OLIVER H. RAMO AT TORNE Y8 VARIABLE SPEED CONTROL FOR TEXTILE CARDING MACHINES Filed June 25, 1965 7 Sheets-Sheet 6 FIG? IN VE N TOR OLIVER H. RAMO BY ATTORNEYS Jan. 23, 1968 H R M 3,364,766

YARIABLE SPEED CONTROL FOR TEXTILE CARDING MACHINES Filed June 25, 1965 7 Sheets-Sheet 7 INVENTOR.

OLIVER H. RAMO 029562 2%w a4oz, @WM 2 wade I ATTORNEYS United States Patent Ofi ice 3,364,766 Patented Jan. 23, 1968 3,364,766 VARIABLE SPEED CONTROL FOR TEXTILE CARDING MACHINES ()llver H. Ramo, North Abington, Mass., assignor to Abingtou Textile Machinery Works, North Abington, Mass., 2 Massachusetts trust Filed June 25, 1965, Ser. No. 466,915 10 Claims. (Cl. 74-23017) ABSTRACT OF THE DISCLOSURE A double variable pitch diameter pulley in the drive of a dotfer from the liclzerin of a textile carding machine together with a control operated by an operator for controlling the variable speed pulley to reduce the doffer speed from one rate to another and keep it at the reduced rate so long as force is being applied to the control by the operator, the control having incorporated therein a compression spring which is compressed by the force applied by the operator and which, when the applied force is released, automatically returns the pulley to its original condition to return the dolfer to its original speed at a rate of doffer speed change not exceeding 5 r.p.m. per second. The double variable pitch diameter pulley is mounted on a rocker arm which is rocked through a linkage in which the compression spring is located around a threaded rod of the linkage between a shoulder on the rod and a fixed shoulder. The rate of doffer speed change upon release of the applied force is adjustable by adjusting spring compression. The limits of movement of the double variable speed pulley are also adjustable to adjust the reduced doffer speed and normal doffer speed.

The present invention relates to a variable speed control device for textile carding machines. More particularly, it relates to such a device for controlling the speed of the dotfer, particularly in cotton and synthetic fiber carding machines.

Many cotton and synthetic textile carding machines are presently being run at high production rates, e.g. 20 to 40 doffer r.p.m., as compared to what are commonly referred to as regular production rates, e.g. 6 to 12 doifer r.p.m.

These high production rates present a problem of manually piecing up the sliver following an end down. The flow of fibers drawn to the web condensing trumpet is at such a rapid rate that an excessively large amount of fibers will collect behind the trumpet before the piecingup can be completed. This rapid collection of an excessive amount of fibers makes piecing-up difiicult and may cause damage to the card parts.

An object of the present invention is to overcome this problem in a simple, inexpensive and foolproof manner by means of a mechanism which can be easily installed on an existing left or right hand cotton card without special equipment. The same simple mechanism will convert an existing card designed for regular production rates into a high production machine. Moreover, it permits simple adjustment of production rates in infinitely small increments over a relatively wide range, e.g. from 8.9 to 40 r.p.m., without interruption in production, i.e., while the card is in production. Such range may include the original regular rate of production of the machine prior to installation of the mechanism and may extend to about 2 /2 to 4 /2 times or more its original rate.

This is achieved in accordance with the present inven ion by means of a variable speed pulley assembly, preferably a double variable pitch diameter pulley assembly, which is installed in the dotfer drive between the lickerin shaft and the doifer gear and by means of which the speed of the dolfer can be quickly and conveniently temporarily reduced by the operator for and during a piece-up operation, whereafter the higher operating dofter speed is restored automatically in a controlled manner. Since the feed roll is driven from the dolfer, the rate of feed by the feed roll is also slowed down with the dotfer. A control for the double variable pitch diameter pulley is conveniently located at the front of the card Where the operator can easily operate it to slow down the dolfer while performing a piecing-up operation and to restore dotfer speed after piece-up is completed.

Preferably, the control is foot operated to leave the operators hands free to perform the piecing-up operation, the variable pitch diameter pulley being operated to slow down the doffer by the pressure of the foot and automatically operated to restore the higher doffer speed in a controlled manner when the pressure of the foot has been released.

The entire assembly can be added to the carding machine by a few bolts and bolt holes in the carding machine frame to convert a card designed for a regular production rate into a high production card capable of being temporarily slowed down during piece-up to the regular production rate.

When it was attempted to utilize a variable speed control for the doifer to temporarily slow down production in this manner for piece-up, it was found that when the higher dc-ifer speed is restored after piece-up, the sliver weight, during and shortly after restoration of such higher speed, became lighter than the intended standard sliver weight. This loss in sliver weight is gradually restored as the card continues to run at the higher production speed. With a very rapid change from low to high production speed, after piece-up, the loss in sliver weight can be so great that the end may break down again.

Accordingly, it is an object of this invention to overcome this problem of piecing-up the sliver at high production speeds.

It is also an object of this invention to minimize the problem of sliver weight variation due to the loss in sliver weight caused by too rapid an increase in doifer speed from the slow piece-u speed to the high production speed.

This is achieved by automatically controlling the rate of increase in speed of the dotfer from its slower piece-up speed to its higher normal speed to a value not greater than about 5, preferably not greater than about 4.0 r.p.m. per second. Optimum results are achieved where the rate of increase in dotfer speed is not greater than about 2.5 to 3.0 r.p.m. per second.

Means are provided for easily adjusting this rate of speed increase of the dolfer after piece-up without interrupting production.

The simplicity of design and in installing the mechanism of the present invention as Well as the versatility in production rates achieved thereby are important advantages.

Other objects and advantages will become apparent from the following description and accompanying drawings by way of example, of a preferred embodiment of the invention.

In the drawings:

FIG. 1 is a view in perspective of the lower and front part of the side of a Saco-Lowell cotton card with the speed control mechanism of the present invention installed in the doffer drive from the lickerin;

FIG. 2 is a side view in perspective of a part of the speed control mechanism of FIG. 1;

FIG. 3 is a partial section in elevation of the speed control mechanism of FIG. 1 during normal operation of the carding machine at a high production rate;

FIG. 4 is a view like FIG. 3 with the dolfer slowed down for a piece-up operation;

FIG. 5 is an end view of the speed control mechanism of FIG. 1 during normal operation of the carding machine at a high production rate; v

FIG. 6 is a view like FIG. 5 with the doifer slowed down for a piece-up operation;

FIG. 7 is a cross sectional view of the double variable pitch diameter pulley of FIG. 1 with the center plate of the pulley shown in broken lines when the doifer is in low speed piece-up position;

FIG. 8 is an exploded view of the complete double variable pitch diameter pulley assembly of FIG. 1;

FIG. 9 is an exploded view of the control for the double variable pitch diameter pulley of FIG. 1;

P16. 10 is a view in perspective showing the manner in which the speed control mechanism of FIG. 1 can be mounted on the side of the carding machine.

With reference to the figures, 2 represents the side frame of a S'aco-Lowell cotton carding machine, the doifer gear of the carding machine being designated as 4, the calender gear as 6, the two idler gears between the doffer gear and calender gear as 8 and 10, the dotfer pulley as 12, the doffer production or barrow gear driving the doffer gear 4 from the pulley 12 and attached to the shaft of pulley 12, as 14, and the pulley attached to the lickerin shaft 16, as 18. Pulley 13 is mounted on the lickerin shaft for rotation therewith by means of a split adapter bushing 19.

Located in the drive for the doiier between the lickerin pulley 18 and the doffer pulley 12 is a double variable pitch diameter pulley assembly 20 made up of a first variable pitch diameter pulley 22 driven from the lickerin pulley 18 by a V-belt 24 and a second variable pitch diameter pulley 26 which drives a pulley 28 by a V-belt 30. Pulley 28 is mounted on the same rotatable pulley shaft 32 as pulley 34, which drives the doffer pulley 12 by the belt 36. The opposite inner faces of pulley 18 and pulley 28 are sloped, e.g. to accommodate the sloped, erg. 15, sides 29 of V-belts 24 and 30.

The variable pitch diameter pulleys 22 and 26 and the pulleys 28 and 34 are mounted on a horizontally disposed U-shaped bracket 38. Each leg of the U-shaped bracket forming the sides of the bracket has the cross-sectional shape of an inverted L to provide a vertical wall 51, the upper edge of which extends horizontally outwardly into a horizontal wall 53. U-shaped bracket 38 has an integral cross piece 40 and is bolted at one side to the underside of a horizontal leg 41 of a piece of angle iron 42 by two bolts 44 passing through two horizontal, longitudinal, elongated slots in the angle iron leg 41 and two elongated slots in horizontal wall 53 of the bracket, which latter slots extend in a direction perpendicular to the slots in the angle iron. The other vertical leg 41a, of angle iron 42 is in turn bolted to the side frame 2 of the card by two bolts 46 passing through horizontal, longitudinal, elongated slots in such other leg. Cross piece 40 comprises a vertical wall and forms a hole 48 and a channel 50 in the bracket 38.

The double variable pitch diameter pulley 22 and 26 is made up of a center sheave plate 52 and two end sheave plates 54 and 56 one on either side of the center plate 52. The three sheave plates are non rotatably mounted on a bushing 58, which in turn is rotatably mounted on shaft 69. The end plates 54 and 56 are also held securely against shoulders 66 on the periphery of bushing 58 by means of two tie rods with nuts 68 passing through holes in the three plates, the center plate 52 being slidable with respect to such tie rods. This prevents any axial sliding movement of the end plates with respect to bushing 58 :but permits axial sliding movement of center plate 52 on bushing 58.

Variable pitch diameter pulley 22, which receives the V-belt 24, is formed by sheave plates 52 and 54 and variable pitch diameter pulley 26, which receives the V-belt 30, is formed by plates 52 and 56. As aforesaid, center sheave plate 52 is adapted to slide axially and reciprocally 0n bushing 58 towards and away from the end sheave plates 54 and 56 to inversely vary the effective pitch diameters 4 of the pulleys 22 and 26 as will be described more fully hereinafter.

Bushing 58 is adapted to slide axially on the shaft 60 in order to insure horizontal alignment of the double variable pitch diameter pulley 22-26 with the pulleys 18 and 26 at all times.

In FIGS. 1, 2, 3, 5 and 7, the center plate 52 is moved to the limit of its travel toward end plate 56 and away from end plate 54 so that the effective pitch diameter of pulley 22 is a its minimum and the effective pitch diameter of pulley 26 is at its maximum which results in maximum dofier speed, whereas in FIGS. 4 and 6, the center plate 52 is moved to the limit of its travel toward end plate 54 and away from end plate 56 so that the eifective pitch diameter of pulley 22 is at its maximum and the effective pitch diameter of pulley 26 is at its minimum which results in the minimum doifer speed.

The center portions of the opposite faces of the center plate 52 are provided with axially extending hubs 62 which are received in recesses 64 in the inner faces of end plates 54 and 56 at the limits of travel of the center plate, as shown in FIG. 7. The opposite faces of the center plate 52 radially beyond the hubs 62 and the inner face of each end plate 54 and 56 radially beyond the recess 64 have a 15 slope 69, which corresponds to the 15 slope of the sides 29 of the V-belts 24 and 30, which engage such sloped faces of the plates. Accordingly, the V-belts 24 and 30 are wedged in the pulleys 22 and 26 as well as the pulleys 18 and 28.

The ends of shaft 60 are received in holes 70 in the ends of a pair of flat parallel rocker arms 72 rigidly joined together by two integral, flat cross walls 74, the rocker arm assembly being represented as '76. The ends of shaft 60 are non-rotatably secured in holes 70 by means of a pair of holding screws 78 passing through the split ends of the rocker arms 72. The length of bushing 58 is shorter than the distance between arms 72 to permit sliding movement of the bushing on shaft 60.

Rocker arm assembly 7 6 is pivotally mounted on bracket 38 by means of a pivot pin 80 passing through holes 81 in the arms 72 whereby the arm assembly 76 is adapted to swing about the pin 80. The ends of pin 80 are rotatably received in holes 84 in the opposite inner faces of walls 51 of bracket 38 defining the opening or hole 48, as shown. Collars 82 are secured on pin 80 inside and adjacent the inner faces of the arms 72 by means of set screws. The rocker arm assembly 76 extends vertically through such opening 48, as shown, the opening being large enough to permit the desired range of swinging motion of the rocker arm assembly 76. Pivot pin 80 is located close to the end of the bracket 38 closest to the pulley 18.

The driven pulley 28 is mounted on the other end of bracket 38 in the channel 50 of the bracket 38 by means of shaft 32, the reduced diameter ends 88 of which are rotatably mounted in a pair of self aligning, sealed ball bearings 86 in bearing support members or housings 90, which are secured to the outer vertical surfaces of the walls 51 of bracket 38, as shown. The inner raceways of ball bearings 86 are located below the walls 51 so that the shaft 32 is located slightly below the end portion of bracket 38. The pulley 28, which receives the V-beit 30, is secured to the shaft 32 by means of a set screw 93 that bears on the set screw flat 92 of shaft 32.

Also, secured to the rotatable shaft 32 in the same way is the spool shaped pulley 34 which receives the flat belt 36.

Both pulleys 28 and 34 extend upwardly between the walls 51 of the bracket 38, as shown.

The lower ends of rocker arms 72 are provided with holes 94 which receive the body diameter of a pin 96 having reduced diameter ends 95. The body diameter of pin 96 is non-rotatably secured in holes 94 by holding screws Q8 threaded in the arms 72. The reduced ends 95 of pin 96 extend laterally beyond holes 94 and hence beyond the outer faces of rocker arms 72. Rotatably mounted on the protruding end 95 of pin 96 closest to the carding machine is a flat block 100 secured on such end of the pin 96 by means of a cotter pin or the like (not shown).

The threaded end of a control rod 102 (FIG. 9) is threaded into a threaded hole 154- in an end face of the block 109. A lock nut 107 secures rod 102 in adjusted position to block 100. Rod 192 is made up of two parts, 18 and 196, connected by a turnbuckle assembly 168 and extends along the side of the carding machine toward the delivery or front end thereof (see FIG. 1). The other threaded end of rod 102 is pivotally attached to the end of a control rocker arm 110 by means of a clevis 112 and clevis pin 114, the other end of control arm 110 being non-rotatably secured on the end of a horizontal pedal rod 116 by means of a holding screw 118. Pedal rod 116 is rotatably mounted in a pair of spaced bearing members 129 secured to the lower front of the card frame by threaded bolts 131. Non-rotatably secured on pedal rod 116 by means of holding screw 124 is the end of a foot pedal 126. Collars 128 non-rotatably secured by means of set screws to the pedal rod 116 on each side of the bearing member 120 closest to arm 110 prevent axial movement of the pedal rod in the bearing members 120.

Nuts 130 adjustably secure the end of rod 106 to the clevis 12.

Arm 110 is provided with two or more clevis pin-receiving holes 132 spaced along the length of the arm 111) from the axis of pedal rod 116 to adjust the position of the clevis pin 114 along the arm 110.

The end of pedal rod 116 is received and non-rotatably secured in a hole at the lower end of arm 110. Pedal rod 116 is also received and non-rotatably secured in a hole in the end of pedal 126.

Pedal rod 116 extends alon the floor across part of the front or delivery end of the card machine and the pedal 126 is conveniently located near the floor close to the coiler where the operator can step on it to operate the double variable pitch diameter pulley to slow down the dolfer while he performs a piece-up operation, as described more fully below.

Pivotally mounted on pin 96 (FIG. 8) between the arms 72 of rocker arm assembly 76 is a threaded rod 134 which is integrally provided at an end with a hollow cylinder 136, the axis of which is crosswise to the axis of the threaded rod 134 to provide a T-shape, as shown. The threaded rod 134 extends from the periphery of the cylinder 135 midway between the ends of the cylinder. The pin 96 is received in the bore of cylinder 136 for rotation of the cylinder about the pin. Two collars 133 are nonrotatably secured by means of set screws (not shown) to the pin 96 at each end of cylinder 136 and between the ends of the cylinder and the inner faces of the lower ends of arms 72.

Rod 134 is threaded throughout its length and is threaded through a threaded hole 1 40 (FIG. 3) in the end wall 141 of a hollow cylindrical spring housing 142 housing a compression coil spring 144, one end of which engages the end wall 141 and the other end of which engages the vertical fixed lower end portion 146 of a bracket 148, the other vertical upper end portion 150 of bracket 148 being secured to the vertical wall 40 of bracket 38 by threaded bolts 152. Rod 1 4 extends through an oversized hole 154 in the lower end portion 146 of bracket 148, and is provided with a nut 156 having an integral internally threaded sleeve 158 which extends through hole 154 and which is adjustably threaded on the rod 134 to provide a stop or shoulder which engages bracket 146 to limit movement of the rod 134 to the right as viewed in FIG. 3, the rod being urged in this direction by the compression spring 144. The limit of the right hand movement of rod 134 can be adjusted by adjusting the position of nut 156 along the rod so that such nut is an adjustment nut. Lock nut 169 locks the adjustment nut 155 in adjusted position.

The compression of spring 144 can be adjusted by threading the threaded spring housing 142 to the right or left along the rod 134 and locking it in adjusted position by lock nut 143.

It is apparent that the lickering pulley 18 drives the variable pitch pulley 22, which drives the variable pitch pulley 26 which drives the pulley 23, which drives the pulley 34, which drives the pulley 12, which drives the dotfer, the feed roll of the card (not shown) being driven from the doffer.

It will be seen that by rocking the rocker arm assembly 76 about its pivot pin 86, the double variable pitch diameter assembly 22-26 mounted on the end of such armis moved reciprocally toward and away from the pulleys 18 and 28 depending on the direction of rock.

When the rocker arm and variable pitch diameter pulley assembly 2226 are in the position shown in FIGS. 1, 2, 3, 5 and 7, which is the limit of travel of the assembly 22-26 in a counterclockwise direction for any particular setting of adjustment nut 156, the pitch diameter of pulley 22 is at its lowest value for such setting whereas the pitch diameter of pulley 26 is at its highest value. This is the normal high production operating condition, e.g., 30 or 40 rpm. Compression spring 144 normally urges the rod 134 and hence the rocker arm assembly 76 to this normal high production position. As aforesaid, this limit of the range of movement of the double variable pitch diameter pulley 2242s and the rocker arm assembly 76 may be adjusted by adjusting the position of nut 156.

After an end down or on starting up the card when the operator desires to piece-up, he presses down on the pedal 126 to rock arm 116 counterclockwise and thereby rock rocker arm assembly 76 clockwise. This moves the variable pitch diameter pulley assembly 22-2zi toward pulley l8 and away from pulley 28 to the slow-down po sition shown in FIGS. 4 and 6. In effect, the distance between pulley axes 6d and 16 is decreased and the distance between pulley axes 6t) and 32 is increased. This forces the pulley belt 31) radially inwardly in pulley 26 between plates 52 and 56 to decrease the pitch diameter of pulley 26, as shown in FIGS. 4 and 6. This forces the center plate 52 toward end plate 54 and away from end plate 56 to apply a compression force to the V-belt 24. The V-belt 24 is thereby forced or squeezed radially outwardly to increase the pitch diameter of pulley 22 by virtue of the sloped sides thereof and the corresponding sloped sides of the plates 52 and 54. In elfect, the sloped sides of the V-belt 2- slide radially outwardly along the sloped faces as of the plates 52 and 54. By decreasing the effective pitch diameter of pulley 26 and increasing the effective pitch diameter of pulley 22 in this way, the speed of the doffer is decreased from its normal high production speed to the low piece-up speed, e.g. from 40 to 8.9 r.p.m. in the particular embodiment shown. However, the invention is not limited to any particular doffer r.p.m.s. By pressing down less on pedal 126, doffer speeds between 40 and 8.9 r.p.m can be temporarily achieved. By adjusting the position of lever 116 or the turnbuckle 108, the slow-down speed for piece-up can be achieved when the pedal is pressed fully down.

It is noted that the frictional resistance of the V-belt 24 to the aforesaid radially outward sliding movement thereof resists the aforesaid clockwise rotation of arm assembly 76 to cause a time delay in the movement of the double variable pitch diameter pulley from its normal high production position shown in FIGS. 1, 2, 3, 5 and 7 to its slow-down speed and piece-up position shown in FIGS. 4 and 6, when the operator presses on pedal 126, as aforesaid.

It is noted that the aforesaid movements of the center plate 52 and belts 24 and 3t) tend to cause the portions of the belts in the pulleys 22 and 26 to move laterally toward the carding machine and to the left, as viewed in FIGS. 6 and 7. However, since all three plates are mounted on bushing 58 for free sliding movement axially on shaft 60 whereas the pulleys 18 and 28 cannot move axially, the

three plates and the bushing 58 are forced to slide axially on shaft 60 in a direction away from the carding machine and to the right in FIGS. 5, 6 and 7 to preserve the belt alignment of pulley 22 with pulley 18 and pulley 26 with pulley 28. Thus, the double variable pitch diameter pulley assembly 22-26 is self aligning.

Once the doffer has been slowed down, as aforesaid, the operator performs a piece-up operation while keeping his foot on pedal 126 to thereby retain the dolfer at its slow piece-up speed.

Upon completion of piece-up, the operator releases the pedal 126, whereupon the compression spring 14-4 moves the arm assembly 76 counterclockwise and the arm 11% clockwise until nut 156 engages bracket 146. Movement of arm assembly 76 counterclockwise moves the double variable pitch diameter pulley assembly 22-26 away from pulley 18 and toward pulley 28 to its normal high production operating position, as determined by the setting of nut 156 and as shown in FIGS. 1, 2, 3, and 7, to thereby force V-belt 24 radially inwardly in pulley 22 between plates 52 and 54 to decrease the pitch diameter of pulley 22, as shown in FIGS. 1, 2, 3, 5 and 7. Center plate 52 is thereby forced away from plate 54 and toward plate 56 to thereby drive the V-belt 3t) radially outwardly to increase the pitch diameter of pulley 26, as shown in FIGS. 1, 2, 3, 5 and 7. Accordingly, the doffer speed is returned to its normal high production rate.

The frictional resistance against the aforesaid radially outward movement by the belt 30 resists the aforesaid movements of the belts and plates and the aforesaid counterclockwise movement of the arm assembly 76 by the compression spring 144 to delay the time it takes for the double variable pitch diameter pulley assembly 22-26 to move from its slow-down position shown in FIGS. 4 and 6 to its normal high production position shown in FIGS. 1, 2, 3, 5 and 7 after the pedal 126 is released. In effect, this delays the time it takes for the doffer rpm to increase from its slow-down, piece-up speed to its normal high production speed.

The size, strength and compression of spring 144 and the proportions of the arm assembly 76 from its fixed pivot 80 to the pivot pin 69 and the pivot pin 96 are selected so that the rate of speed increase of the doffer from its slow-down, piece-up speed to its normal high production speed, when the operator releases the pedal 126, is not greater than 5 rpm. per second and preferably is not greater than 4 rpm. per second. In the embodiment shown, the rate of doffer speed increase is 2.3 r.p.m. per second and it is best not to exceed a rate of doifer speed increase of from 2.5 to 3 rpm. per second.

This is quite important because it has been found that if the rate of dofier speed increase is much more than 5 rpm. per second a sharp reduction in the sliver Weight occurs to such an extent as to be likely to cause an enddown and other undesirable results. A maximum rate of doffer speed increase of 4.0 r.p.m. per second is in most cases a safer maximum and a maximum rate of dolfer speed increase of 3.0 r.p.m. per second is even safer. The proper size, weight and compression of the spring to provide a doffer speed increase of not more than 5 or 4 or 3 or 25 rpm. per second can be easily arrived at for the particular carding machine involved and the particular rocker arm and double variable pitch diameter pulley assembly used. If the lever arm between holes 94 and 81 of arm assembly 76 is increased and the lever arm between holes 81 and 7%) are decreased, a smaller size spring or a smaller compression can be used. The same is true if the slopes 69 of the plates 52, S4 and 56 and the corresponding slopes of the sides of the V-belts are increased to thereby decrease the resistance of the double pulley 22-2 to movement of the arm assembly '76 by the spring 144.

The rate of dotfer speed increase can be adjusted by adjusting the axial position of the end wali .i ii of housing 142 on rod 134 to vary the compression of spring 144.

8 Thus, by threading the end wall 141 to the right, as shown in FIG. 3, the spring compression is decreased and the rate of doffer speed change is decreased. By threading the end wall 141 to the left, the spring is compressed more and the rate of dolfer speed change is increased.

The time delay cause by the resistance of the double pulley 22-26 and the compression spring 144 to movement of the double pulley 22-26 toward pulley 18 and away from pulley 28 when the pedal 126 is pressed down by the operator also ensures that the rate of dorfer speed decrease will ordinarily not be much greater than 5 rpm. This is not too important for piece-up operation but when it is desired to slow down the doffer while the card is operating, if it is slowed down at a rate greater than 5 rpm. per second, the weight of the sliver increases sharply to the point where an end-down and other difiiculties might occur. This resistance also reduces the risk of accidental slow-down because of the accidental application of slight pressures on the pedal 126.

By adjusting the adjustment nut 156 on rod 134 axially to the right, as shown in FIG. 3, the limit of the movement of the double pulley 22-26 by compression spring i li toward pulley 23 and away from pulley 18 to normal high production speed position is shifted toward pulley 38. Consequently, the pitch diameter of pulley 22 during normal high production operation is increased whereby the normal rates of production and doifer r.p.m. are decreased. On the other hand, by adjustment of nut 156 axially to the left, the normal high production position of pulley 22-26 is shifted toward pulley 28 to thereby increase the normal high production rate of the card. In this way, the production rate of the card can be varied by infinitely small increments over a wide range, e.g. from 2 /2 to 4 /2 times or more the lowest rate, Without stopping the carding machine. The V-belt. i.e., a belt with sloped sides, together with the use of pulleys having correspondingly sloped inner faces makes possible this relatively wide range of adjustment of production rate. By increasing the widths of such belts and by increasing the maximum distance between the center plate and each end plate, as well as the diameter of such plates, the range of speed adjustment can be increased. In the embodiment shown, the outside width of the belt is inch and the slope of each side is 15, i.e., the total angle is 30'. This makes possible a range of 4 /2 times the lowest rate. However, by adjustment of nut 156, a range of 2 /2 times can be achieved. On the other hand, if a maximum range of 2 /2 times is desired, a belt which has an outside width of inch can be used with the same angle of slope. In such case, the sheave plates are designed so that the center plate is located closer to each end plate at the minimum pitch diameter of the pulley formed by such end plate, In effect, this can be achieved by decreasing the fixed distance between the two outside plates.

The application of this speed control to a carding machine, eliminates the former practice of replacing the production or barrow gear 14 with another gear with a greater or less number of teeth, or changing the diameter of the drive pulley usually located on lickerin shaft 16 to obtain the desired production speed.

It may be seen that the mechanism of the invention can be very easily attached by only the two bolts 46 and the two bolts 131 and without special equipment, to an existing card to convert it to a variable high speed card having the slow-down feature of the invention for pieceup. The slow-down speed can be the original speed of the card.

To piece-up the operator need only step on pedal 126 near the coiler can. After piece-up, the card will return to its normal production speed automatically when the foot pedal is released.

The speed control of the invention can also be used in other textile machinery where the speed of a unit must be varied or slowed down to obtain a desired result.

I claim:

1. Speed control mechanism for controlling doffer speed in a textile carding machine comprising a variable speed pulley located in the drive for said doifer, means operable by the operator for applying a force to move said variable speed pulley from one position to another to thereby vary the speed of said dofier from one value to another value, resilient means acting on said variable speed pulley for returning said variable speed pulley from said other position to said one position upon release of said force to thereby return said dotler speed to said one value at a rate of speed change of said dofier not exceeding rpm. per second, said variable speed pulley having means for yieldably resisting said movement thereof by said force from said one position to the other and said movement thereof by said resilient means from said other position to said one position, said resilient means comprising a compression spring which is compressed by said movement of said variable speed pulley from said one position to said other position, said mechanism also comprising means for adjusting at least one of said positions of said variable speed pulley and means for adjusting the rate of speed change of said dorfer by said compression spring, said one value being a higher doifer speed than said other value, said variable speed pulley comprising a double variable pitch diameter pulley, said means for moving said double variable pitch diameter pulley comprising a rocker arm on which said double variable pitch diameter pulley is mounted and a linkage system connected at one end to said arm and at the other end to a control member adapted to be operated by the operator to apply said force and thereby slow down said doffer during piece-up, said compression spring automatically returning said dofier speed to its higher value upon release of said force by said operator, said linkage system comprising a threaded rod extending through said compression spring, said rod having a shoulder engaged by an end of said spring, the other end of said spring engaging a fixed shoulder.

2. A mechanism according to claim 1, said threaded rod passing through an oversized hole in said fixed shoulder, means for adjusting the position of said shoulder on said rod to adjust the compression of said spring and thereby the rate of speed change of said doficr from said other value to said one value when said force is released.

3. A mechanism according to claim 2, said rod having a stop member adjustable along the length thereof and located on the side of said fixed shoulder opposite from said compression spring to limit the movement of said rod by said compression spring upon release of said force to thereby permit adjustment of said one value without interruption in production.

4. A mechanism according to claim 2, said linkage system also comprising a second rod operably connected to said arm at one end and to said control member at its other end, said control member being located at the front of said carding machine and operable by the operator to move and hold said double variable pitch diameter pulley to and in said other position while piecing-up.

S. A mechanism according to claim 1, said pulley comprising a double variable pitch diameter pulley having sloped faces and belts having correspondingly sloped sides, the higher speed value of said doller being at least 2.5 times the value of the lower speed value.

6. Speed control mechanism for controlling dofifer speed in a textile carding machine in which the dolfer is driven from the lickerin, said mechanism comprising a first pulley adapted to be operably connected in driven relation with the lickerin and a second pulley adapted to be connected in driving relation with the doffer shaft of said carding machine, a double variable pitch diameter pulley located between said first and second pulleys and having a sheave center plate located between and spaced from a pair of sheave end plates to form said double pulley, said center plate forming with one of said end plates 21 first variable pitch diameter pulley of said double pulley and with the other of said end plates at second variable pitch diameter pulley of said double pulley, said center plate being adapted to move axially and reciprocally toward and away from said end plates, a first belt between said first pulley and said first variable pitch diameter pulley, a second belt between said second pulley and said second variable pitch diameter pulley, the opposed faces of said center and end plates engaging the sides of said belts being sloped by an amount corresponding to the slopes of the sides of said belts, means for reciprocally moving said double variable pitch diameter pulley over a range of positions toward and away from said first and second pulleys to force either of said belts, depending on the direction of movement of said double variable pitch diameter pulley, radially inwardly between its pulley plates and the other or" said belts radially outwardly between its pulley plates to thereby change the pitch diameters of said variable pitch diameter pulleys inversely with respect to each other, whereby the speed of said doller is changed, the radially inward movement of said either belt forcing said center plate to move axially toward the end plate associated with the other belt to force said other belt radially outwardly by virtue of the slopes of the sides of said other belt and of the plates with which it is associated, said radially inward movement of said either belt being resisted by friction between said other belt and the plates with which it is associated, resilient means ur ing said double variable pitch diameter pulley toward one of the limits of said range, means operable by the operator to apply a force to said double variable pitch diameter pulley to move it toward the other limit of said range against said resilient means, the size, strength and loading of said resilient means being selected so that when said force is released, said resilient means will return said variable speed pulley to said one of said limits at a rate at which the rate of speed change of said doffer does not exceed about 5.0 r.p.m. per second, said resilient means comprisin a compression spring, said mechanism including means for adjusting the rate of movement of said double variable pitch diameter pulley by said compression spring when said force is released to thereby control the rate or" speed change of said dofier, and also including means for adjusting said range of movement of said double variable pitch diameter pulley to thereby adjust the speed range of said dofier, said double variable pitch diameter pulley being mounted on a rocker arm pivotally mounted on the frame of said carding machine, a linkage system connecting said arm with a member operable by the operator to apply said force to said arm to rotate it in one direction and thereby move said double variable pitch diameter pulley to said other limit of its range, said linkage system comprising a rod attached at one end to said arm and having a shoulder engaged by an end of said spring, the other end of said spring engaging a fixed shoulder, said spring being compressed between said shoulders by said movement of said double variable pitch diameter pulley toward said other limit of its range by said force; means for adjusting the position of at least one of said shoulders to adjust the compression of said spring to thereby adjust the rate of speed change of said doffer when said force is released, said rod having an adjustable stop member which engages said fixed shoulder to adjust said one limit of said range.

7. A mechanism according to claim 6, said rod being threaded, a spring housing adjustably threaded to said rod, said spring housing having an end wall engaged by said one end of said spring, said end wall comprising said shoulder of said rod, adjustment of said housing axially on said rod adjusting the compression of said spring, thereby adjusting the rate of speed change of said dolier when said force is released, said fixed shoulder comprising a bracket having an oversized hole for receiving said rod, said stop member comprising a threaded member adjustably threaded on said rod and engaging said bracket to limit movement or" said rod by said compression spring.

8. A mechanism according to claim '7, said threaded member comprising a nut having a sleeve extending around said rod and through said oversize hole in said fixed bracket.

9. A mechanism according to claim 7, movement of said double variable pitch diameter pulley to said other limit of its range by said force against said compression spring being effective to increase the pitch diameter of said first variable pitch diameter pulley and decrease the pitch diameter of second variable pitch diameter pulley, whereby the speed of the dofier is reduced, movement of said double variable pitch diameter pulley to said one limit of its range by said compression spring upon release of said force being effective to decrease the pitch diameter of said first variable pitch diameter pulley and increase the pitch diameter of said second variable pitch diameter pulley whereby the speed of the dofier is increased, said one limit being spaced further from said first pulley and closer to said second pulley than said other limit, whereby movement of said double variable pitch diameter pulley from said one limit to said other limit moves said double variable pitch diameter pulley away from said second pulley and toward said first pulley, and movement of said double variable pitch diameter pulley from said other limit to said one limit moves said variable speed pulley away from said first pulley and toward said second pulley.

10. A mechanism according to claim 6, said control 5 member being a foot pedal operable by the operator to reduce the speed of the doiter while he is piecing-up.

References Cited UNITED STATES PATENTS 2,560,013 7/1951 Varga 74 230.17 2,813,433 11/1957 Adams et al 74 230.17 2,885,897 5/1959 Pettigrew 74 230.17 2,927,450 3/1960 PO01 74 230.17 15 2,936,840 5/1960 White 74-23017 2,942,447 6/1960 Rickeletal 74 230.17 3,129,598 4/1964 Buss 74 230.17

FRED C. MATTERN, IR., Primary Examiner.

DAVID J. WILLIAMOWSKY, Examiner.

C. J. HUSAR, Assistant Examiner. 

